New doc instructions, black

[jrzkaminski]

This pull request includes multiple changes to the documentation, primarily focused on adding new tutorials and updating existing ones. The most important changes include the addition of tutorials for autoformatting code with Black, creating documentation with MkDocs, and updating the documentation links in the README files.

Documentation updates:

• README.md: Updated links to documentation tutorials, including new entries for MkDocs and Read The Docs.
• README_en.md: Updated the link to the documentation tutorial to point to the Read The Docs guide.

New tutorials:

• tutorials/black_autoformatting.md: Added a new tutorial for autoformatting Python code using Black, including installation instructions and GitHub Actions configuration.
• tutorials/documentation_mkdocs.md: Added a new tutorial for creating project documentation using MkDocs Material, including setup, configuration, and deployment instructions.

Renamed files:

• tutorials/documentation.md to tutorials/documentation_rtd.md: Renamed the existing documentation tutorial to specify that it is for Read The Docs.